1. Field of the Invention
The present invention relates to an automatic fitting device for assembling a vehicular part, and in particular to an automatic fitting device for assembling a vehicular part, wherein the automatic fitting device comprises spring-biased buttons adapted to be fitted in a bush of a vehicular part such as a trailing arm and then inserted into a vehicular bracket, so that the vehicular part can be automatically assembled.
2. Description of the Prior Art
So-called chassis marriage is typically an assembling process for rendering vehicular parts, such as an engine, a transmission, a fuel tank, a fuel line, and a muffler, to be assembled with a vehicular body. This process involves connecting the engine and the transmission with front-wheels and modularizing the fuel tank, the fuel line and the muffler in unison on the rear-wheels, in addition to the modularization of chassis. Through the chassis marriage, the convenience of working can be enhanced and the working hours can be shortened, thereby reducing the basic costs.
In the conventional chassis marriage as described above, a vehicular bracket positioned at the upper side and a chassis and a power train or the like positioned at the lower side are adapted to be vertically moved toward one another, fitted and interconnected with each other by means of automatic fitting devices.
In the above-mentioned chassis interconnection structure, because all parts are in an upright position, no specific problem will occur in assembling upper and lower parts with each other.
However, several parts, such as a trailing arm 1 of the chassis that performs pivotal movement, cannot be assembled by merely vertically lifting them, because their assembling directions are not vertical but inclined with respect to the ground, as shown in FIG. 1a. 
Therefore, because it is impossible to automatically fit the trailing arm 1 into a vehicular bracket 3, it is unavoidable for an operator to directly assemble the trailing arm 1 with the vehicular bracket 3, whereby the chassis marriage cannot be employed.
In order to overcome this problem, it has been proposed to use chassis brackets 4 each formed with bolting holes 5 for assembling bolts 6 rather than the vehicular bracket 3 so that the trailing arm 1 of the chassis can be vertically mounted, as shown in FIG. 1b. 
However, according to this measurement, the separate chassis brackets 4 will increase the weight and manufacturing costs of the resultant vehicle. In addition, the number of bolts for assembling the chassis brackets is also increased (in order to achieve a proper stability—three bolts are required for each chassis bracket. As a result, the measurement is considered as being inefficient.